1. Field of the Invention
The present invention relates to vehicle lamp systems for use in automobiles or the like.
2. Description of the Related Art
Typically, a vehicle lamp can switch between a low beam and a high beam. The low beam illuminates objects at a close range at a predetermined illuminance. Light-distribution patterns of the low beam are regulated so as not to cause glare to an oncoming vehicle or a leading vehicle, and the low beam is used mainly when the vehicle travels in a city area. Meanwhile, the high beam illuminates objects at a distant, broad range in front at a relatively high illuminance and is used mainly when the vehicle travels at high speed on a road with little oncoming vehicle or little leading vehicle (see, for example, JP2008-137516).
To carry out a fault diagnosis of a lamp unit, there is a demand such that the lamp unit be turned on to illuminate with a high beam upon the engine being started, for example. However, there is a problem in that a high beam may cause glare to a driver of a vehicle present in front of the started vehicle or to a pedestrian.